STE. GENEVIEVE COUNTY, Mo. – A Phelps County woman accused of killing her husband had allegedly plotted his death for months, the Ste. Genevieve County Sheriff’s Office said Tuesday.

Investigators said Susan Armantrout, 41, shot and killed her husband, 36-year-old Aaron Armantrout, and attempted to hide his body.

She was charged Monday, December 17 with first-degree murder, unlawful use of a firearm, and illegal transportation of a corpse.

According to the probable cause statement, a Ste. Genevieve County sheriff’s deputy went to the Armantrouts’ residence on the morning of Friday, December 14 after Aaron reported Susan had been making death threats against him for the last few months. The deputy said Aaron declined to file a formal complaint against his wife despite the deputy’s encouragement.

Around 12 p.m. on Saturday, Aaron Armantrout’s father contacted the sheriff’s office to report that his son was missing. Aaron was supposed to meet with his sister Friday evening but never met with her. Aaron’s brother and sister-in-law went to his house Saturday morning but did not see him. They noticed Aaron’s BMW was missing as well. A family friend has also just left the residence and said the home smelled like bleach.

Deputies went to Aaron Armantrout’s house and immediately noticed a strong odor of cleaning chemicals. The odor was strongest in the master bedroom, which was locked. Once deputies gained access to the bedroom, they noticed an area of the carpet that had been dampened and appeared to have been cleaned.

On Sunday, December 16 around 11:35 p.m., police in Bonne Terre, Missouri contacted the Ste. Genevieve County Sheriff’s Office to report that Susan Armantrout had been located at an acquaintance’s residence and taken into custody. The acquaintance told deputies that Susan arrived at her home hours earlier and admitted to shooting Aaron and putting his body in the trunk of his BMW.

Just after midnight on Monday, December 17, authorities interviewed a friend of Susan’s who said she’d heard Susan say on numerous occasions that she was going to kill her husband. This friend also said Susan admitted to killing Aaron.

Around 10:15 a.m., deputies said Susan Armantrout asked to speak with them and she confessed to Aaron’s murder by shooting him in the head. She said she attempted to clean up the scene of the crime, then dragged Aaron’s body to the garage and hid him in the trunk of his BMW, then drove the vehicle to a storage unit in Potosi. She parked the vehicle inside the storage unit and jammed the lock to the trunk.

During their investigation, deputies interviewed Susan’s mother, who described Susan’s attempt to shoot Aaron in fall 2017 at Lake Hanna in St. Francois County. Susan’s niece told deputies that Susan previously remarked she kept one bullet in her gun and that was for killing her husband.